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very appropriate appellation of the shepherds, for the resemblance is certainly in favour of the Dipper: the four stars in the square forming the bowl, and the other three, the handle.
When the Dipper is on the meridian, above the pole, the bottom lies towards us, with the handle on the right.)
Benetnasch is a bright star of the 2d magnitude, and is the first in the handle. The second, or middle star in the handle, is Mizar, 7° distant from Benetnasch. It may be known by means of a very minute star almost touching it, called Alcor, which appears to be double when seen through a telescope, and of a silver white. The third star in the handle is called Alioth, and is about 440 W. of Mizar. Alioth is very nearly opposite Shedir in Cassiopeia, and at an equal distance from the pole. Benetnasch, Mizar, and Alioth, constitute the handle, while the next four in the square form the bowl of the Dipper.
Five and a half degrees W. of Alioth is the first star in the top of the Dipper, at the junction of the handle, called Megrez; } it is the smallest and middle one of the cluster, and is used in various observations both on sea and land, for important purposes.* At the distance of 440 S. W. of Megrez, is Phad, the rst star in that part of the bottom, which handle.
The stars in this cluster are so well known, and may be so easily described without reference to their relative bearings, that they would rather confuse than assist the student, were they given with ever so much accuracy. The several bearings for this cluster were taken when Megrez was on the meridian, and will not apply at any other time, though their respective distances will remain the
At the distance of 80 W. of Phad, is the westernmost star in the bottom of the Dipper, called Merak. The bright star 50 N. of it, towards the pole, is called Dubhe: but these two, Merak and Dubhe, are, by common consent, called the Pointers, because they always point towards the pole; for, let the line which joins them be continued in the same direction 28° farther, it will just reach the north pole..
The names, positions, and relative distances of the stars in this cluster, should be well remembered, as they will be fre
* When Megrez and Caph have the same altitude, and are seen in the same horizontal line east and west, the polar star is then at its greatest elongation from the true pole of the heavens; and this is the proper time for an observer to take its angle of elevation, in order to determine the latitude, and its azimuth or angle of declination, in order to determine the magnetic variation.
What, on the whole, is an appropriate appellation for it, and why? Describe the position of the Dipper when on the meridian. Describe the position of Benetnasch. What is the next star in the Dipper, and how may it be known? What is the next, or third star in the Dipper? What stars form the bowl and handle of the Dipper? Describe the position and use of Megrez. What star is situated next to Megrez? Describe the position of Merak and Dubhe. What are these stars called, and why?
quently adverted to. The distance of Dubhe, or the Pointer nearest to the north pole, is 2830. The distance between the two upper stars in the Dipper is 100; between the two lower ones is 8: the distance from the brim to the bottom next the handle, is 410; between Megrez and Alioth is 51°; between Alioth and Mizar 410, and between Mizar and Benetnasch, 7°.
The reason why it is important to have these distances clearly settled in the mind is, that these stars, being always in view, and more familiar than any other, the student will never fail to have a standard measure before him, which the eye can easily make use of in determining the distances between other stars.
The position of Megrez in Ursa Major, and of Caph in Cassiopeia, is somewhat remarkable. They are both in the equinoctial colure, almost exactly opposite each other, and equally distant from the pole. Caph is in the colure, which passes through the vernal equinox, and Megrez is in that which passes through the autumnal equinox. The latter passes the meridian at 9 o'clock, on the 10th of May, and the former just six months afterwards, at the same hour, on the 10th of November..
Psi, in the left leg of Ursa Major, is a star of the 3d magnitude, in a straight line with Megrez and Phad, distant from the latter 1210. A little out of the same line, 3° farther, is another star of the 3d magnitude, marked Epsilon, which may be distinguished from Psi, from its forming a straight line with the two Pointers.
The right fore paw, and the two hinder ones, each about 15° from the other, are several y distinguished by two stars of the 4th magnitude, between 10 and 20 apart. These three duplicate stars are nearly in a right line, 20° S. of, and in a direction nearly parallel with, Phad and Dubhe, and are the only stars in this constellation that ever set in this latitude.
There are few other stars of equal brightness with those just described, but amidst the more splendid and interesting group with which they are clustered, they seldom engage our observation.
The whole number of visible stars in this constellation is 87; of which one is of the 1st, three are of the 2d, seven of the 3d, and about twice as many of the 4th magnitude.
HISTORY.-URSA MAJOR is said to be Calisto, or Helice, daughter of Lycaon,
What is the distance of Dubhe from the north pole? Mention the relative distances between the other stars in this group. Why is it important to have the relative distances of these stars from each other well settled in the mind? What is there remarkable in the position of Megrez, and Caph in Cassiopeia? When do they pass the me. ridian? Describe the position of Psi. Where is Epsilon situated, and how may it be distinguished? How are the paws of the Bear distinguished? What is the situation of these stars with respect to Phad and Dubhe? What are the only stars in this constellation that ever set in this latitude? What is the whole number of visible stars in this constellation, and how many of each magnitude?
king of Arcadia. She was an attendant of Diana,* and mother of Arcas, by Ju. piter, who placed her among the constellations, after the jealousy of Juno had changed her into a bear.
"This said, her hand within her hair she wound,
And lest the supplicating brute might reach
How did she fear lodge in woods alone,
And haunt the fields and meadows, once her own!
How often would the deep-mouth'd dogs pursue,
Whilst from her hounds the frighted hunters flew."-Ovid's Met. Some suppose that her son Arcas, otherwise called Bootes, was changed into Ursa Minor, or the Little Bear. It is well known, that the ancients represented both these constellations under the figure of a wagon drawn by a team of horses; hence the appellation of Charles's Wain, or wagon. This is alluded to in the Phenomena of Aratus, a Greek poem, from which St. Paul quotes. in his address to the Athenians:
"The one call'd Helix,† soon as day retires,
Observed with ease, lights up his radiant fires:
* Diana was the goddess of hunting, and the patroness of modesty and chastity :"The huntress Dian,
Fair, silver-shafted queen, for ever chaste,
-set at naught
The frivolous bolt of Cupid; gods and men
Fear her stern frown, and she was queen o' th' woods."-Milton.
The most famous of her temples was that of Ephesus, near Smyrna, in Asia, which was one of the seven wonders of the world. It is related in the Acts of the Apostles, that "Demetrius, a silversmith, who made silver shrines for Diana," endeavoured to excite opposition to the Christian religion, because "this Paul had persuaded much people that they be no gods which are made with hands," and "that the temple of the great goddess Diana should be despised, and her mas nificence should be destroyed, whom all Asia and the world worshippeth. And when they heard these sayings they were full of wrath, and cried out, saying, Great is Diana of the Ephesians! And thus they continuer shouting for the space of two hours." And again, "When the town clerk had appeased the people, he said, Ye men of Ephesus, what man is there that knoweth not how that the city of the Ephesians is a worshipper of the great goddess Diana, and of the image which fell down from Jupiter?"
The "image which fell down from Jupiter," doubtless alludes to the fable that Juno cast her out of heaven, and that Neptune, in pity of her desolate condition, raised the island of Delos, from the Egean sea, for her birth and habitation; for it was in this island that the twins, Apollo and Diana, were born. Diana is therefore sometimes called Delia, from the name of the island that gave her birth. She was represented under the figure of a very beautiful virgin, in a hunting dress, a head taller than any of her attendant nymphs, with a bow in her hand, a quiver suspended across her shoulders, and her forehead ornamented with a silver crescent "which Jews might kiss and infidels adore." The inhabitants of Taurica sacrificed upon her altars all the strangers that were shipwrecked upon their coast. The Lacedemonians yearly offered her human victims till the age of Lycurgus, who changed this barbarous custom of immolation to flagellation. The Athenians generally offered her goats, while others offered white kids and ewes.
"Haste the sacrifice;
Seven bullocks yet unyoked for Phoebus choose,
Who does not bow with grateful veneration at that Christian intrepidity of St. Paul, who risked his life in exposing the delusion and idolatry of the worshippers of the goddess Diana!
It is a remarkable circumstance, that the temple of Diana was burnt to the ground the very day on which Alexander the great was born!
Calisto was a native of the city of Helice, in Achaia, a district near the bay of Co rinth; hence the Greater Bear is sometimes called Helice :
"Night on the earth pour'd darkness; on the sea,
The watchful sailor, to Orion's star
The other, smaller, and with feebler beams,
In the Egyptian planispheres of remote antiquity, these two constellations are represented by the figures of bears, instead of wagons; and the Greeks, who derived most of their astronomical symbols from the Egyptians, though they usually altered them to emblems of their own history or superstition, have, nev ertheless, retained the original form of the two bears. It is said by Aratus, that the Phenician navigators inade use of Ursa Minor in directing their voyages:"Observing this, Phenicians plough the main :"
while the Greeks confined their observations to Ursa Major.
Some imagine that the ancient Egyptians arranged the stars near the north pole, within the outlines of a bear, because the polar regions are the haunts of this animal, and also because it makes neither extensive journeys nor rapid
At what period men began to sail by the stars, or who were the first people that did so, is not clear; but the honour is usually given to the Phenicians. That it was practised by the Greeks, as early as the time of the Trojan war, that is, about 1200 years B. C., we learn from Homer: for he says of Ulysses, when sailing on his raft, that
"Placed at the helm he sate, and mark'd the skies,
It is rational to suppose that the stars were first used as a guide to travellers by land, for we can scarcely imagine that men would venture themselves upon the sea by night, before they had first learned some safe and sure method of directing their course by land. And we find, according to Diodorus Siculus, that travellers in the sandy plains of Arabia were accustomed to direct their course by the Bears.
That people travelled in these vast deserts at night by observing the stars, is directly proved by this passage of the Koran :-"God has given you the stars to be guides in the dark. both by land and by sea."
BERENICE'S HAIR.-This is a beautiful cluster of small stars, situated about 50 E. of the equinoctial colure, and midway between Cor Caroli on the northeast, and Denebola on the southwest. If a straight line be drawn from Benetnasch through Cor Caroli, and produced to Denebola, it will pass. through it.
The principal stars are of between the 4th and 5th magnitudes. According to Flamsted, there are thirteen of the 4th magnitude, and according to others there are seven; but the student will find agreeably to his map, that there is apparently but one star in this group, entitled to that rank, and this is situated about 7° S. E. of the main cluster.
Although it is not easy to mistake this group for any other in the same region of the skies, yet the stars, which compose it are all so small as to be rarely distinguished in the full presence of the moon. The confused lustre of this assemblage
Describe the appearance and situation of Coma Berenices. What are the magnitudes of the principal stars in this cluster? What are they, according to Flamsted and others? How many stars of the 4th magnitude will the student find on the map? Is it easy to mistake this group, and is it visible in presence of the moon?
of small stars somewhat resembles that of the Milky-Way, It contains besides the stars already alluded to, a number of nebulæ.
The whole number of stars in this constellation is 43; its mean right ascension is 185°. It consequently is on the meridian the 13th of May.
The glittering maze of Berenice's Hair ;
HISTORY.-Berenice was of royal descent, and a lady of great beauty, who married Ptolemy Soter, or Evergetes, one of the kings of Egypt, her own brother, whom she loved with much tenderness. When he was going on a dangerous expedition against the Assyrians, she vowed to dedicate her hair to the goddess of beauty, if he returned in safety. Sometime after the victorious return of her husband, Evergetes, the locks which agreeably to her oath, she had deposited in the temple of Venus disappeared. The king expressed great regret at the loss of what he so much prized; whereupon Conon, his astronomer, publicly reported that Jupiter had taken away the queen's locks from the temple, and placed them among the stars.
"There Berenice's locks first rose so bright,
The heavens bespangling with dishevelled light."
Conon, being sent for by the king, pointed out this constellation, saying, "There behold the locks of the queen." This group being among the unformed stars until that time, and not known as a constellation, the king was satisfied with the declaration of the astrononier, and the queen became reconciled to the partiality of the gods.
Callimachus, an historian and poet, who flourished long before the Christian era, has these lines as translated by Tytler:
"Immortal Conon, blest with skill divine,
THE CROW.-This small constellation is situated on the eastern part of Hydra, 15° E. of the Cup, and is on the same meridian with Coma Berenices, but as far S. of the equinoctial as Coma Berenices is N. of it. It therefore culminates at the same time, on the 12th of May. It contains nine visible stars, including three of the 3d magnitude and two of the 4th.
This constellation is readily distinguished by means of three stars of the 3d magnitude and one of the 4th, forming a trapezium or irregular square, the two upper ones being about 310 apart, and the two lower ones 6° apart.
What does its lustre resemble? What is the number of stars in this constellation, and hen is it on the meridian? Where is the Crow situated? When is it on the ineridian? What are the number and magnitude of its stars? How is it readily distinguished?